Great video Ben. One question. How you would get the rope "hang points" to stay stationary when you adjust the "hang amount"? My rope hang points move up & down whilst my hooks are still stationary. I will probably have a play trying to work it out but I'd like to see how you'd do it, seeing you know what your doing & I'm a complete noob, whoops, I meant apprentice;-)
Thanks for the nice tutorial: I have one question. I recreated your setup with the foreach loop(16:45 in the video), but I would need a modification. I want that the slack amount is driven by the length of each segment. How can extract the data of segment length. Thanks for your help
Hi Ben, thank you for making this video! I am trying to wrap my head around VOP and VEX. QUESTION: at about 5:00 you said "we gonna first look at ptnum and numpt.... convert to float ... drag out Float node..." Probably super-beginner question--how would i know this in the first place? Can you point me in the right direction where to look for that? It seems to me that that is the missing piece of the puzzle for me--i can follow directions in the video, but i do not understand why/how, so if i had to do this simple action on my own i would not know where to start. Are there mathematical formulas that i need to learn first or something? I watched a few VOP tutorials, and everyone just pulls out the different nodes, plugs in different wires, and BAM!, it all works. But how do they know to use those specific nodes? That is the answer i am searching. ... AND if I know all the formulas, would it not just be easier to use Wrangle and write VEX? Any advise you can provide, i would really appreciate it. Thank you for your time!
Hi Maxim! This is something that is really different for everyone, but for myself (and in general I think this does apply to most people) it's something that is picked up naturally just from continuing to work though it. And it never really "goes away" since there are always new problems to solve in Houdini, you just naturally develop a sense of where and what to look for over time. What's the phrase, "10,000 hours of practice makes a master"? So really just keep at it and keep asking questions. :-) From a broader standpoint, it's important to understand the different ways that Houdini and other 3D software packages store and manipulate data. For example, every object is composed of Primitives, which are composed of Points, which in turn contain Vertices. In Houdini, each Point is assigned a unique number and stores a P (position) attribute, which is a a vector that contains 3 floats values for the X, Y, and Z coordinates of the Point. See www.sidefx.com/docs/houdini/model/attributes.html for a great breakdown of this hierarchy. Many nodes also provide local variables that are useful for nodes of that type. The local variable "ptnum" represents the Point number of the current Point being processed, and the local variable "numpt" represents the total number of Points that exist in the node. See www.sidefx.com/docs/houdini/network/expressions for more explanation on these variable types. These are useful variables to have since we have set the VOP to run over all Points. If we were iterating over Primitives, we could use the "primnum" and "numprim" local variables to the same effect instead. As for converting those variables to floats: the Divide node (like many of the nodes in VOPs) inherits the output type from its inputs. So, because we are dividing the Point number (integer) by the number of Points (integer) if we leave them as integers, the Divide node will output an integer, which will in this case always round to either 0 or 1. So in order to return the float value and get the real decimal values, we need to convert the inputs to floats. Understanding the reasons for this is a mix of basic numerical data, some simple math, and familiarizing yourself with the nodes in Houdini. I highly recommend exploring and reading through the Houdini nodes documentation. www.sidefx.com/docs/houdini/nodes/vop/index.html
@@GoingProcedural wow, thank you for such a detailed response! I really appreciate your explanation and i am looking forward to learning from your videos
Howdy Aamir! Is there a particular expression you are struggling with? I also intended to provide example files to pair with these videos, so I'll probably get on that sometime soon, as it would probably be helpful.
One of the best videos ever!!! Had to watch a few times and go over so I could grasp all the info but well worth it! One question. 27:00 I noticed that if the merge input was reversed, the Join node would create a nasty looking line between the edge lines. I’m a newbie, so is there an explanation to this? Thank you !
Howdy Kijas! The Join node has a Blend parameter that is checked on by default that joins and fuses points based on their sort order. So, in cases where we are not sorting the points such that the overlapping points are numerically adjacent, you can sometimes get this behavior. You can watch this in action if you move the Bias slider around to get a better idea of what is going on. This could be solved by turning off Blend, which will not fuse the points, but still combine the primitives, and then placing a Fuse node below it to clean up the overlapping points, and then the point order (which is partially determined by the Merge order in this case) will not matter.
Ben House Thank you so much, I’m trying to get into Hdn. And trying to understand as much as I can. I from from Maya and Nuke so I know how those work, but this is a whole new ball park. Appreciate your videos, going over them now. I might ask a few more questions if you don’t mind :D.
Is there a particular reason that using 'add' + 'resample' instead of 'line' at first place? My confusion is, it seems like 'line' has every functions that you're using in this case.
No reason other than old habits and just demonstrating a different way to do something. You are correct that you could just as well do this using a Line node.
Man would be nice if you spend a little more time explaining the operations and their logic, inside the VOPS. This set up is not very easy for a Houdini beginner Artist user without an understanding of some of the logic
![[Intermediate Beginner Tutorial] Overview of For-Loops](http://i.ytimg.com/vi/AGnh5747DNE/mqdefault.jpg)
Stupendously great series, perfectly tutored. Thank you so much, and please do keep up the great work Ben.
This video was exceptional. I learned a lot about programing and using Houdini. Thank you!
Thanks for this super useful lesson ! I learnt a ton today !!
Excellent tutorial. Thanks!
easy to learn , great thanks
Thank you for this tutorial ! do you have a video to make tank tracks rolling over terrain ?
Great video Ben. One question. How you would get the rope "hang points" to stay stationary when you adjust the "hang amount"? My rope hang points move up & down whilst my hooks are still stationary. I will probably have a play trying to work it out but I'd like to see how you'd do it, seeing you know what your doing & I'm a complete noob, whoops, I meant apprentice;-)
Thanks for the nice tutorial: I have one question. I recreated your setup with the foreach loop(16:45 in the video), but I would need a modification. I want that the slack amount is driven by the length of each segment. How can extract the data of segment length. Thanks for your help
Hi Ben, thank you for making this video! I am trying to wrap my head around VOP and VEX.
QUESTION: at about 5:00 you said "we gonna first look at ptnum and numpt.... convert to float ... drag out Float node..." Probably super-beginner question--how would i know this in the first place? Can you point me in the right direction where to look for that? It seems to me that that is the missing piece of the puzzle for me--i can follow directions in the video, but i do not understand why/how, so if i had to do this simple action on my own i would not know where to start.
Are there mathematical formulas that i need to learn first or something? I watched a few VOP tutorials, and everyone just pulls out the different nodes, plugs in different wires, and BAM!, it all works. But how do they know to use those specific nodes? That is the answer i am searching. ... AND if I know all the formulas, would it not just be easier to use Wrangle and write VEX? Any advise you can provide, i would really appreciate it.
Thank you for your time!
Hi Maxim! This is something that is really different for everyone, but for myself (and in general I think this does apply to most people) it's something that is picked up naturally just from continuing to work though it. And it never really "goes away" since there are always new problems to solve in Houdini, you just naturally develop a sense of where and what to look for over time. What's the phrase, "10,000 hours of practice makes a master"? So really just keep at it and keep asking questions. :-)
From a broader standpoint, it's important to understand the different ways that Houdini and other 3D software packages store and manipulate data. For example, every object is composed of Primitives, which are composed of Points, which in turn contain Vertices. In Houdini, each Point is assigned a unique number and stores a P (position) attribute, which is a a vector that contains 3 floats values for the X, Y, and Z coordinates of the Point. See www.sidefx.com/docs/houdini/model/attributes.html for a great breakdown of this hierarchy.
Many nodes also provide local variables that are useful for nodes of that type. The local variable "ptnum" represents the Point number of the current Point being processed, and the local variable "numpt" represents the total number of Points that exist in the node. See www.sidefx.com/docs/houdini/network/expressions for more explanation on these variable types. These are useful variables to have since we have set the VOP to run over all Points. If we were iterating over Primitives, we could use the "primnum" and "numprim" local variables to the same effect instead.
As for converting those variables to floats: the Divide node (like many of the nodes in VOPs) inherits the output type from its inputs. So, because we are dividing the Point number (integer) by the number of Points (integer) if we leave them as integers, the Divide node will output an integer, which will in this case always round to either 0 or 1. So in order to return the float value and get the real decimal values, we need to convert the inputs to floats. Understanding the reasons for this is a mix of basic numerical data, some simple math, and familiarizing yourself with the nodes in Houdini. I highly recommend exploring and reading through the Houdini nodes documentation. www.sidefx.com/docs/houdini/nodes/vop/index.html
@@GoingProcedural wow, thank you for such a detailed response! I really appreciate your explanation and i am looking forward to learning from your videos
useful
good video for someone already good at writing expression. I have a difficulty reading the expressions due to bad resolution.
Howdy Aamir! Is there a particular expression you are struggling with? I also intended to provide example files to pair with these videos, so I'll probably get on that sometime soon, as it would probably be helpful.
One of the best videos ever!!! Had to watch a few times and go over so I could grasp all the info but well worth it! One question. 27:00 I noticed that if the merge input was reversed, the Join node would create a nasty looking line between the edge lines. I’m a newbie, so is there an explanation to this? Thank you !
Howdy Kijas! The Join node has a Blend parameter that is checked on by default that joins and fuses points based on their sort order. So, in cases where we are not sorting the points such that the overlapping points are numerically adjacent, you can sometimes get this behavior. You can watch this in action if you move the Bias slider around to get a better idea of what is going on. This could be solved by turning off Blend, which will not fuse the points, but still combine the primitives, and then placing a Fuse node below it to clean up the overlapping points, and then the point order (which is partially determined by the Merge order in this case) will not matter.
Ben House Thank you so much, I’m trying to get into Hdn. And trying to understand as much as I can. I from from Maya and Nuke so I know how those work, but this is a whole new ball park. Appreciate your videos, going over them now. I might ask a few more questions if you don’t mind :D.
Can you please make videos that shows only one vex function for example nearpoints,length,point etc
Is there a particular reason that using 'add' + 'resample' instead of 'line' at first place? My confusion is, it seems like 'line' has every functions that you're using in this case.
No reason other than old habits and just demonstrating a different way to do something. You are correct that you could just as well do this using a Line node.
Man would be nice if you spend a little more time explaining the operations and their logic, inside the VOPS. This set up is not very easy for a Houdini beginner Artist user without an understanding of some of the logic